I've never tested this, but is it possible you'd see better 'per- delete' cost with a larger batch?
Maybe try the maximum number of entities in a batch (500, I think), calculate the average cost per entity, and see if that's any better? On Feb 20, 11:41 am, kang <[email protected]> wrote: > Thanks, Andrew. But after the change, it still costs me 2130cpu_ms > 2112api_cpu_ms :) > > On Sat, Feb 20, 2010 at 5:22 PM, Andrew Chilton <[email protected]>wrote: > > > > > > > On 20 February 2010 21:21, kang <[email protected]> wrote: > > > I'm going to clear the datastore. I use the following code: > > > old_date = datetime.datetime(2009,10,1) > > > old_updates = SomeUpdate.all().filter("updated <",old_date).fetch(20) > > > db.delete(old_updates) > > > it costs me nearly 1982cpu_ms 1945api_cpu_ms every time. Is it normal? > > > You might be able to save some time by using a keys_only query. See > > this for details. > > >http://code.google.com/appengine/docs/python/datastore/modelclass.htm... > > > Cheers, > > Andy > > > -- > > contact: Andrew Chilton > > website:http://www.chilts.org/blog/ > > > -- > > You received this message because you are subscribed to the Google Groups > > "Google App Engine" group. > > To post to this group, send email to [email protected]. > > To unsubscribe from this group, send email to > > [email protected]<google-appengine%2Bunsubscrib > > [email protected]> > > . > > For more options, visit this group at > >http://groups.google.com/group/google-appengine?hl=en. > > -- > Stay hungry,Stay foolish. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
